gemini-cli/integration-tests/flicker.test.ts

/**
 * @license
 * Copyright 2025 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

import { describe, it, expect } from 'vitest';
import { TestRig } from './test-helper.js';
import { join } from 'node:path';

describe('Flicker Detector', () => {
  it('should not detect a flicker under the max height budget', async () => {
    const rig = new TestRig();
    rig.setup('flicker-detector-test', {
      fakeResponsesPath: join(
        import.meta.dirname,
        'flicker-detector.max-height.responses',
      ),
    });
    try {
      const run = await rig.runInteractive();
      const prompt = 'Tell me a fun fact.';
      await run.type(prompt);
      await run.type('\r');

      const hasUserPromptEvent = await rig.waitForTelemetryEvent('user_prompt');
      expect(hasUserPromptEvent).toBe(true);

      const hasSessionCountMetric = await rig.waitForMetric('session.count');
      expect(hasSessionCountMetric).toBe(true);

      // We expect NO flicker event to be found.
      const flickerMetric = rig.readMetric('ui.flicker.count');
      expect(flickerMetric).toBeNull();
    } finally {
      await rig.cleanup();
    }
  });
});